Apparatus for the production of tubes.



No. 770,997. I PATENTED SEPT. 27, 1904 A. E. BECK & G. TOWNSEND.

APPARATUS FOR THE PRODUCTION OF TUBES.

APPLICATION FILED NGV. 24. 1903.

No. 770,997. PATENTED SEPT. 27, 1904. A. B. BECK & G. TOWNSEND.

APPARATUS FOR THE PRODUCTION OF TUBES.

v APPLICATION FILED NOV.2-1, 1903. N0 MODEL. 1 a SHEETS-SHEET 2.

5/ vxa Jrr m/ t .No. 770,997. PATENTED SEPT. 27, 1904,.

A. E. BECK & G. TOWNSEND. 2

APPARATUS FOR THE PRODUCTION OF TUBES.

APPLIOATION FILED H0124, 1903.

N0 MODEL 3 SHEETS-SHEET 3.

UNITED STATES Patented September 27, 1904.

PATENT OFFICE.

APPARATUS FOR THE PRODUCTION OF TUBES.

SPECIFICATION forming part of Letters Patent No. 770,997, datedSeptember 27, 1904.

Application filed November 24, 1903. Serial No. 182,501. (No model.)

1'0 all whom it may concern:

Be it known that we, ARTHUR EDWARD BEoK and GEORGE TOWNSEND, subjects ofthe King of Great Britain and Ireland, residing at 33 Newhall street, inthe city of Birmingham, England, have invented certain new and usefulImprovements Relating to the Manufacture of Metal Tubes, (for which wehave filed an application in Great Britain, No. 26,637, bearing dateDecember 3, 1902,) of which the following is a specification.

This invention comprises an improved means for the production of tubesdirectfrom molten or plastic metal, and is particularly applicable tothe production of weldless steel tubes for various purposes.

In a simple form a plant or apparatus for the production of tubes inaccordance with this invention comprises a tWyer-like or water cooledcentral core having a diameter equal to the bore or internal diameter ofthe required tube and arranged within a cylinder or chamber of such aninternal diameter that the annular space between the cylinder-wall andthe aforesaid core serves as the die ormold for the formation of thetube. Within the space between the cylinder and the core (which may bevaried in dimensions either by increasing the diameter of the cylinderor reducing the diameter of the core) an annular ram or plunger isinserted and arranged for reciprocation in any convenient manner. Duringsuch reciprocation the ram is made to pass over an aperture formedthrough the cylinder-wall to admit the metal to be operated upon from acontainer communicating With the said aperture. Thus when the plant isin operation a small quantity of the metal flows or is drawn into thecylinder on each outstroke of the ram after the latter has uncovered theadmission-aperture; but during the instroke of the ram the aperture isclosed or cut ofi", and by the continued inward movement of the ram themetal in advance of it is pressed along the aforesaid die or mold. Oneach double stroke or complete reciprocation of the ram the same actionis repeated, so that a tube may be made of any desired length, for

as the tube is gradually delivered or pushed off from the outer end ofthe core and out of the cylinder orchamber as increment upon incrementis added to it by the pump-like action of the ram the lengths of thecylinder and the core do not limit the length of tube.

In another form of plant or apparatus suitable for the manufacture ofsteel tubes in accordance with this invention a reciprocating mandrel isarranged Within the twyer-like or water-cooled core, and both the coreand the cylinder are made of tapered form at the extrusion or deliveryend. The annular space forming the mold or die is thus made to vary inarea or cross-section in order that the metal shall be subjected to anaction akin to that which takes place during forging and likeoperations. The end portion of the reciprocating mandrel aforesaid ismade on its outstroke to pass beyond the front or delivery end of thecore, but on its instroke to pass within the core, and is therebycooled. Preferably the outstrokes of the annular ram and the mandrel aremade to synchronize and the instroke of the latter to commence slightlyin advance of that of the former. As in the previous case, the tube isformed increment by increment on each complete reciprocation of the ramand is gradually and intermittently pushed from one end of the die tothe other. During its gradual movement along the tapered or conicalportion of the mold the varying cross section throughout such portionproduces a molecular action throughout the metal somewhat akin to thatwhich takes place during forging and like operations, whereby it isincreased in density and improved for most services for which tubes arerequired. On leaving the mold the tube is still hot and may, ifrequired, be subjected to reducing or other processes either with orwithout additional heating.

Referring to the three accompanying sheets of explanatory drawings,Figure 1 is a sectional elevation, and Fig. 2 a sectional plan, of anapparatus constructed for the manufacture of tubes in accordance withour invention in which the core and the cylinder are tapered and acentral mandrel is provided. Fig. 3 is a sectional end view on the lineA B, Fig. 1.

The same referencelctters in the different views indicate the same orsimilar parts.

(6 is a cylinder with an annular ram or plunger 7).

c is a chamber fitting within a housing or holder d.

The motor-cylinder u and the housing (7 of the operating-cylinder c areconnected together by screw tie-bars 0, provided with abutment or thrustnuts f and A core 71/, having one end bolted or secured to themotorcylinder (6, projects longitudinally through the center of theannular ram 7/, as illustrated, While in a central aperture formedlongitudinally through the said core 7i itself is placed a mandrel '11,adapted for independent reciprocation by a supplementary motor-cylinderj. One end of the mandrel 1 is arranged as or provided with a plunger orpiston Z: for working within the said supplementary cylinder j. Theouter or operative end of the ram 6 is preferably provided with adetachable nosepiece Z, having its fore part adapted for entering themouth of the operating cylinder or chamber 0. The bore of the cylinder 0at its mouth or admission end is parallel for a short distancecorresponding with the length of the plunger-stroke. From the innerextremity of such parallel portion to the opposite or extrusion enc /1.0., to a die at, which is secured at such end by the abutment ar thebore of the cylinder is made to a tapered form. The nose or end portionof the core it which enters the cylinder 0 is also made tapered, asshown, and the said nose is preferaby made detachable by means of ascrewjoint. The end of the mandrel i which projects beyond the nose ofthe core /2 and through the die m is also preferably made detachable bymeans of a screw -joint. The core it is cooled by the circulation ofwater through the same e. by means of pipes 0, arranged within channelsformed longitudil'ially through the core, the inner ends of the saidchannels communicating with the water-cooling apertures, as illustrated,in the tapered nose of the core it. Oooling-apertures, withwater-circulating pipes and conncctionsp, are also formed and arrangedaround the housing or holder (Z of the operating cylinder or chamber c.The return stroke of the ram 7) on its movement away from theoperating-cylinder c is effected by means of a pair of drawbackcylinders(1, within which are 'plungers connected to the opposite ends of across-head r, fixed upon the main or annular ram Z), as shown. Suitableplugs or fittings are provided upon the cylinder (0, the supplementarycylinder j, and the return or drawback cylinders q for the connection ofthe hydraulic supply-pipes with suitable automatic or other valves forregulating the admission and discharge of water to or from the variouscylinders. Ordinary leather or other packings are employed wherenecessary. The drawings show the ram 7) at the end of its inward stroke.Its nose-piece Z is therefore at its outer position with respect to theoperatingcylinder 0.

During the inward stroke of the ram 6 with respect to its cylinder (0the lateral port or aperture 25 in the operating cylinder or chamber 0is opened. A quantity of molten metal from the supply in the containerat, which may be heated, if necessary, for the purpose of keeping themetal therein at the proper consistency, is then drawn or carriedthrough the said port into the cylinder 0. The container u can be formedin the housing or holder (Z of the cylinder 0, as illustrated. In somecases it may be found advantageous to provide more than one port if fromthe container a, and it is also an advantage to furnish the containerand port or ports with a removable liner, as will be readily understood.On the outward stroke of the ram 5 With respect to its cylinder a or itsinward stroke with respect to the cylinder or chamber 0 the port t isclosed or covered by the ramnose Z, and the metal entrapped in thechamber is pressed toward the die at at the extrusion or discharge end.By the continuation of the reciprocatory action of the apparatus themolten metal is gradually withdrawn increment by increment from thecontainer u to the cylinder or chamber 0, subjected to a number ofintermittent compressions in the said chamber, and finally extrudedtherefrom as a uniform or continuous tube, such as o, in a step-by-stepmanner. By maintaining the supply of molten metal to the container 2/,at the proper temperature the tube may be pro-- duced of any desiredlength, or as it is extruded in a continuous form the tube may be cutinto lengths, as required.

By the arrangement and combination of mold parts, as aforesaid, and thespeed of reciprocation and length of stroke of the ram we provide for agradation or regulation of temperature throughout the inclosed metaloperated upon, so that as it flows from the discharge end of the die itis sufficiently rigid to retain its shape, while at the opposite end itis sufficiently molten or plastic to permit each incoming addition orincrement of metal to readily unite with the preceding increment for theformation of a continuous tube. The said gradation or regulation oftemperature also prevents any such solidification of the metal withinthe mold as to completely resist extrusion and render the apparatusliable to breakage or stoppage. At meal-times or other requiredstoppages of the plant the chamber 0 can be readily cleared of the metalby admitting a charge of sand, soapstone, or other material that can bereadily extruded in a cold state.

Our invention in the form illustrated by the drawings is particularlyapplicable to the production of tubes of steel and other hard ordifiicultly-fusible metals which cannot be satisfactorily extruded on acommercial-scale as and by the means heretofore employed with softmetals. By the use of our invention in the form above referred to thefollowing desiderata are achieved, viz: (a) The metal is cast in annularshape and forged subsequently. (b) The annular casting is of greaterdiameter than the finished tube, and so back pressure is produced whichenables the ram to make the tube homogeneous. (0) Theinternal andexternal portions of the mold are made suificient in cooling effect toproperly reduce the temperature. (cZ) Each increment of plastic orliquid metal ejects the previous one. (0) The mold is so arranged thatthe metal is liquid at the casting end and solid at the finishing end,and f there is intermittent cessation of work, so that the mandrel andother parts are cooled.

Having thus described our invention, What we claim as new, and desire tosecure by Letters Patent, is

1. In the manufacture of tubes direct from molten or plastic metal, thecombination consisting of an operating cylinder or chamber, a centralcooling-core, a mandrel within said core and reciprocating independentlythereof, a mold formed by the said cylinder the core and mandrel for thereception of the molten or plastic metal, and an annular ramreciprocating in the said mold whereby the said metal is subjected torepeated compressive workings and gradually carried step by step throughthe mold and discharged therefrom in a continuous length, substantiallyas described.

2. In the manufacture of tubes direct from molten or plastic metal, thecombination consisting of an operating cylinder or chamber, a centralcooling-core, a reciprocating mandrel, a die, a mold formed by the saidcylinder the core the mandrel and die for the reception of the molten orplastic metal, and an annular ram reciprocating in the said mold wherebythe said metal is subjected to repeated Workings and gradually carriedstep by step through the mold and discharged therefrom in a continuouslength, substantially as described.

3. In the manufacture of tubes direct from molten or plastic metal, thecombination consisting of an operating cylinder or chamber, a centralcooling-core, amandrel, amold formed by the said cylinder the core andthe mandrel for the reception of the molten or plastic metal, an annularram, a motor adapted to reciprocate the said ram in the said moldwhereby the metal therein is subjected to repeated compressiveworkingsand gradually carried step by step through the mold anddischarged therefrom in a continuous length, and to reciprocate also thesaid mandrel, substantially as described.

I. In the manufacture of tubes direct from molten or plastic metal, thecombination consisting of an operating cylinder or chamber, a centralcooling-core, a mandrel, a die, a mold formed by the said cylinder thecore the mandrel and die for the reception of the molten or plasticmetal, an annular ram, a hydraulic cylinder and connections adapted toreciprocate the said mandrel, and hydraulic cylinders and connectionsadapted to reciprocate the said ram in the said mold whereby the metaltherein is subjected to repeated compressive Workings and graduallycarried step by step through the mold and discharged therefrom in acontinuous length, substantially as described.

In Witness whereof we have hereunto set our hands in presence of twowitnesses.

ARTHUR EDWARD BECK. GEORGE TOWNSEND.

Witnesses:

JOHN MORGAN, HENRY WVoRWooD.

